My Miata has a removable hard top that works quite well and doesn't leak. Here is how it is set up:
It's front joint is about 2" from the top edge of the windshield. There is a rubber gasket there attached to a flange that the edge of the hardtop sits on, and it is cinced down by two large suitcase style latches. The same edge also meets up with the doors, and the top gasket for the windows is on the hardtop. The rear of the top is cinched down by two more latches right behind the doors level with the bottom of the side windows. There is a gasket with a lip on the hardtop that covers a flange on the body and on the back there are two slot-and-key fasteners that are there to align the top when installing it. The top is rigid with a solid glass rear window with a defroster in it, and it's a really good setup. I would copy it if I was doing that to my truck.
